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I'am wrapping a java lib into clojure, but i have problems dealing with variable length arguments. Say,
TestClass.aStaticFunction(Integer... intList){/*....*/} How could i call this function in clojure?
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Before JDK 5, variable length arguments could be handled in two ways: One was using overloading, other was using array argument. There can be only one variable argument in a method. Variable argument (Varargs) must be the last argument.
Varargs can be used when we are unsure about the number of arguments to be passed in a method. It creates an array of parameters of unspecified length in the background and such a parameter can be treated as an array in runtime.
Varargs is a short name for variable arguments. In Java, an argument of a method can accept arbitrary number of values. This argument that can accept variable number of values is called varargs. The syntax for implementing varargs is as follows: accessModifier methodName(datatype… arg) { // method body }
Since Java varargs are actually arrays, you can call vararg functions in Clojure by passing an array.
You could convert a Clojure seq (maybe by using Clojure's variety of variable argument functions) into an array:
(TestClass/aStaticFunction (into-array Integer [(int 1),(int 2)])) or
(defn a-static-function-wrapper [& args] (TestClass/aStaticFunction (into-array Integer args)) Or make an array and set its indices manually
(TestClass/aStaticFunction (doto (make-array Integer 3) (aset 0 first-element) (aset 1 second-element) (aset 2 third-element))) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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